Geologic Wonders of the National Parks, site 1-6

1. Hawaii Volcanoes National Park, Hawaii - Contains the world's most massive mountain, Mauna Loa at 13,677 feet and Kilauea, the world's most active volcano. Measured from its base on the seafloor, Mauna Loa rises over 30,000 feet, more than a thousand feet higher than Mount Everest. In contrast to explosive continental volcanoes, the more fluid and less gaseous eruptions of Kilauea and Mauna Loa produce awe inspiring, fiery fountains and rivers of molten lava that visitors can observe from a safe distance. Kilauea produces enough volcanic material every day to cover a football field to the height of the Washington Monument. More

2.
Grand Canyon National Park, Arizona - Hailed as one of the Seven Wonders
of the World, the Grand Canyon exhibits the largest section of geologic time
on earth. Hiking to the bottom, one passes through a third of the planet's
age. The Park also contains excellent exposure of the world renowned Great
Unconformity, an impressive angular unconformity, occupying 1.2 billion years
in the rock record. The gap in the rock record straddles the Precambrian - Cambrian
boundary and is found nearly everywhere around the globe. More

3. Mount Rainier National Park, Washington - Has the largest collection of glaciers on one peak in the contiguous U.S. The mountain has 25 named glaciers and 50 smaller, unnamed glaciers and ice fields. In the Lower 48, Mount Rainier National Park has the thickest and most voluminous glacier, Carbon Glacier, and the glacier with the greatest surface area Emmons Glacier. It is one of the most accessible places to view glaciers up close. More

4. Great Sand Dunes National Park and Preserve, Colorado - Houses the tallest sand dunes, over 750 ft., in North America and one of the most fragile and complex dune systems in the world. Sand and sediments deposited in the San Luis Valley were picked up by the fierce winds blowing towards the Northeast. The sands were deposited at the base at the Sangre de Cristo Mountains, which barred their passage, creating the enormous dunes in the high mountainous setting. More

5. Yellowstone National Park, Wyoming, Montana, and Idaho - The Yellowstone Caldera is the largest in North America. The Yellowstone hotspot has actually produced three calderas in the Yellowstone region, the youngest of which is nearly 80 kilometers long and 50 kilometers wide. There have been caldera-forming eruptions roughly once every 600,000 years, and future eruptions are expected. More

6. Aniakchak National Monument, Alaska - Aniakchak is located on the Alaska Peninsula, part of the Aleutian volcanic arc. The Aniakchak caldera is one of the youngest calderas in North America, erupting last in 1931 and is one of the finest examples of a dry caldera in the world. The Aleutian arc itself is one of the simplest and most visible subduction zones on Earth. More